Key Takeaways
- Personalized immunotherapy takes a patient’s own immune cells, genetically modifies them to recognize and attack cancer cells, and reintroduces them into the body — unlike traditional immunotherapy, which uses broader, non-specific immune-boosting approaches.
- In a clinical trial of colorectal cancer patients, personalized immunotherapy caused tumor shrinkage in 3 out of 7 patients — a significant improvement over traditional immunotherapy, which typically only achieves tumor stability (no growth, but no shrinkage either).
- The approach works by genetically engineering lymphocytes (immune cells including T cells and B cells) with receptors that allow them to correctly identify and target cancer cells — overriding the ability of mesothelioma to “turn off” immune function.
- Because the modified cells are the patient’s own lymphocytes — not externally grown lab cells — there is less risk of rejection and a greater chance that the immune cells will reproduce with their genetic modifications intact.
- While the trial was conducted in colorectal patients, the researchers deemed the findings applicable to all solid tumors, including mesothelioma. If validated in mesothelioma-specific trials, this approach could allow mesothelioma to be managed more like a chronic disease.
- Tumor shrinkage — not just stability — represents a new frontier in mesothelioma treatment that has not been achievable through traditional immunotherapy alone.
Personalized Immunotherapy vs. Traditional Immunotherapy
Traditional immunotherapy utilizes the body’s natural immunity in different, non-specific ways. This could look like increasing the number of certain antibodies, restoring anti tumor capacities to immune cells, or injecting lab-grown immune cells into a patient’s body. Immunotherapy has proven largely successful, especially in the context of mesothelioma treatment: it often results in tumor stability, which means no growth beyond the tumor’s original size. Additionally, immunotherapy has less side effects than other systemic forms of treatment, like chemotherapy.
A downside of immunotherapy is that it’s not always as successful as chemotherapy, despite recent strides in efficacy and safety. Chemotherapy works by intercepting all cells’ reproduction, so it affects all bodily cells—not just cancerous ones. Immunotherapy only targets cancerous cells, which seems effective in theory. In application, it doesn’t work as well as a systemic targeting of all bodily cells. This has been a challenging tradeoff for care providers, especially considering that chemotherapy is, on the whole, more effective than immunotherapy, although it produces more side effects.
A new study published by Nature Medicine looked at a clinical trial conducted in patients with colorectal cancer. Despite the niche group of participants, the researchers deemed the results as applicable to all patients with solid tumors, mesothelioma included. They found that an individualized approach to immunotherapy—a modified iteration of the original approach—proved largely successful.
In this context, individualized immunotherapy refers to the genetic engineering of lymphocytes found in patients. Lymphocytes are a class of immune cells that have many specialized iterations (T cells and B cells, mainly). On a macroscopic scale, lymphocytes are responsible for a.) detecting antigens; and b.) producing antibodies to target and kill said antigens. In mesothelioma patients, the functionality of these lymphocytes is often impaired or completely usurped, as characteristic of mesothelial immune environments. The reason that mesothelioma tumors are able to sustain themselves and grow is because they’re able to “turn off” lymphocyte function.
In this study, the lymphocytes were engineered to contain receptors for detecting colorectal cancer cells. This means that they were able to a.) correctly identify cancerous cells as being cancerous; and b.) could coordinate an immune response as a result. Instead of introducing external immune cells—so, cells that weren’t already circulating in a patient’s body—researchers were able to alter existing cells. By effect, this means there’s less of a chance for the body to reject the cells and there’s a greater chance that the immune cells will successfully reproduce with their genetic modifications.
In three of the seven patients enrolled in the trial, their tumors actually reduced in size. This is monumental: in other immunotherapy studies, the tumors remained stable, meaning they didn’t experience any growth or shrinkage. The findings from this study suggest that personalized immunotherapy could help reduce tumor size, which hasn’t been conceptualized as a treatment possibility for mesothelioma patients. With a long latency period, delayed diagnosis, and often grim prognosis, the shrinkage of mesothelioma tumors is a serious milestone in treatment capacities.
Implications for Future Treatment
Importantly, these studies will have to be conducted in the context of mesothelioma for them to be implemented. Mesothelioma could be managed like a chronic disease if treatments could shrink tumors. Additionally, if the lymphocytes are able to reproduce with their genetic alterations intact, there wouldn’t have to be multiple iterations of treatment for it to be successful. Personalized immunotherapy is revolutionizing the ways in which we think about and research new treatment strategies.
If you or a loved one has been diagnosed with mesothelioma or another asbestos-related disease, we are here to help. Our website offers useful information regarding types of asbestos-related diseases, hospitals to receive treatment in Pennsylvania, a variety of different treatment options, and more. For more information or for legal help, please call us at (800) 505-6000 or simply fill out our contact form.
Frequently Asked Questions
What is the difference between personalized and traditional immunotherapy?
The key difference is specificity:
- Traditional immunotherapy uses broad approaches — increasing antibody counts, restoring general antitumor function, or introducing lab-grown immune cells. Drugs like Keytruda and Opdivo remove the “brakes” on the immune system so it can fight cancer more effectively.
- Personalized immunotherapy takes a patient’s own immune cells, genetically engineers them to contain specific receptors for detecting that patient’s cancer cells, and reintroduces them into the body. Because the cells are the patient’s own — not external — there is less chance of rejection and a greater chance of the modifications being passed on when the cells reproduce.
How does personalized immunotherapy work?
The process involves genetically modifying lymphocytes — a class of immune cells that includes T cells and B cells. In a healthy immune system, lymphocytes detect antigens (foreign threats) and produce antibodies to destroy them. In mesothelioma patients, cancer cells hijack this system and “turn off” lymphocyte function. Personalized immunotherapy restores and enhances this function by engineering the lymphocytes with receptors that can correctly identify cancer cells as threats — even when the cancer is trying to hide from the immune system.
Did personalized immunotherapy shrink tumors?
Yes. In a clinical trial published in Nature Medicine, 3 of 7 colorectal cancer patients who received personalized immunotherapy experienced actual tumor shrinkage. This is a significant finding because traditional immunotherapy for mesothelioma typically achieves tumor stability (the cancer stops growing but doesn’t shrink). The ability to reduce tumor size opens up treatment possibilities that were not previously considered achievable for mesothelioma patients.
Can these results be applied to mesothelioma?
The researchers believe yes — in principle. Although the trial was conducted in colorectal cancer patients, the findings were deemed applicable to all patients with solid tumors, which includes mesothelioma. However, mesothelioma-specific trials would need to be conducted before this approach could be implemented as a standard treatment. Mesothelioma presents unique challenges — particularly its ability to suppress immune function — that would need to be validated in dedicated clinical studies.
Could mesothelioma be managed as a chronic disease?
Potentially. If personalized immunotherapy can consistently shrink mesothelioma tumors — and if the genetically modified lymphocytes can reproduce with their modifications intact — it may be possible to manage mesothelioma as a chronic condition rather than a terminal one. This would mean ongoing treatment that keeps the cancer controlled, similar to how diabetes or HIV is managed today. While this is still a future possibility rather than a current reality, the tumor shrinkage results from the clinical trial represent a meaningful step in that direction.
How is this different from immunotoxin therapy?
Both are forms of engineered immune therapy, but they work differently:
- Personalized immunotherapy — modifies the patient’s own existing immune cells to recognize and attack cancer. The modified cells can potentially reproduce, creating an ongoing immune response.
- Immunotoxin therapy (e.g., LMB-100) — introduces externally engineered immune cells loaded with toxic compounds that target and kill cancer cells directly. The body may reject these external cells before they reach the tumor.
Personalized immunotherapy has the advantage of using the patient’s own cells, reducing rejection risk. Immunotoxin therapy has the advantage of carrying a direct toxic payload.
What should I do if I’ve been diagnosed with mesothelioma?
If you or a loved one has been diagnosed with mesothelioma, understanding the full range of treatment options — including emerging approaches like personalized immunotherapy — is an important step. For information about your legal options, call (800) 505-6000 or fill out our contact form for a free consultation.
